/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */
package com.eluup.flume.sink.elasticsearch;

import java.util.Map;

import org.apache.commons.lang.StringUtils;
import org.apache.flume.Event;
import org.apache.flume.event.SimpleEvent;
import org.joda.time.DateTimeUtils;

import com.google.common.collect.Maps;

/**
 * {@link org.apache.flume.Event} implementation that has a timestamp. The
 * timestamp is taken from (in order of precedence):
 * <ol>
 * <li>The "timestamp" header of the base event, if present</li>
 * <li>The "@timestamp" header of the base event, if present</li>
 * <li>The current time in millis, otherwise</li>
 * </ol>
 */
final class TimestampedEvent extends SimpleEvent {

	private final long timestamp;

	TimestampedEvent(Event base) {
		setBody(base.getBody());
		Map<String, String> headers = Maps.newHashMap(base.getHeaders());
		String timestampString = headers.get("timestamp");
		if (StringUtils.isBlank(timestampString)) {
			timestampString = headers.get("@timestamp");
		}
		if (StringUtils.isBlank(timestampString)) {
			this.timestamp = DateTimeUtils.currentTimeMillis();
			headers.put("timestamp", String.valueOf(timestamp));
		} else {
			this.timestamp = Long.valueOf(timestampString);
		}
		setHeaders(headers);
	}

	long getTimestamp() {
		return timestamp;
	}
}
